In order to save space on a respective host substrate, multiple integrated circuits or dies may be combined to produce a single multi-die assembly by vertically stacking the dies on top of each other. In such an instance, a voltage received from the host substrate typically powers each die in the multi-die assembly.
In certain instances, the magnitude of voltage required to power each die in a stack may vary, in which case, the host substrate may provide multiple different voltages to power the multi-die assembly. External generation of the voltages on the host substrate may be undesirable because it requires that the board designer provide an external voltage regulator with respect to the multi-die assembly, increasing platform costs and complexity. In other words, external circuitry with respect to the multi-die assembly can be used to generate appropriate voltages to power the different dies in the multi-die assembly.
As an alternative to requiring external generation of the multiple voltages, conventional dies can be configured to include charge pump circuitry to convert a single received voltage into multiple different supply voltages. Via connectivity in the multi-die assembly, the internally generated voltages are then used to power the different dies in the multi-die assembly. Use of one or more charge pumps in a multi-die assembly is undesirable because they are typically inefficient and thus waste power.